1. Field of the Invention
The present invention relates generally to phone communication using a home network, and more particularly, to a method and an apparatus for authenticating a counterpart when phone communication is performed using the home network.
2. Description of the Related Art
Generally, the home network is realized with a private network based on the Internet Protocol (IP), and connects various types of devices, such as Personal Computers (PCs), intelligent products, and wireless devices used at home with one network through a common virtual computing environment called middleware and controls them.
The middleware enables communication between various digital devices through connecting the devices with a peer-to-peer scheme, and Home AV Interoperability (HAVI), Universal Plug and Play (UPnP), Java Intelligent Network Infra-structure (JINI), and Home Wide Web (HWW) have been suggested for the middleware.
Each device in a computing environment established through the UPnP middleware is allocated a protocol from a server according to Dynamic Host Configuration Protocol (DHCP) or an address selected by an automatic IP designation function and performs a communication between devices and a search on a network based on the allocated protocol or address.
A UPnP network is the most widely utilized home network technology and defines a UPnP device and a UPnP service based on a protocol between the UPnP device and the UPnP service. The UPnP network includes a Controlled Device (CD), which is a home network device connected to an IP-based home network and controlled, and a Control Point (CP), which is a device for controlling the CD. The control point is a device for controlling the controlled device and is an element for requesting an event and receiving the event. The controlled device is a device performing a determined function based on the request of the control point and is an element for transmitting an event to a control point requesting the event when a state of the controlled device is changed.
An operation between devices in the existing UPnP network includes an advertisement process, a discovery process, a description process, a control process, and an eventing process.
The advertisement process is a process of reporting a new controlled device to other devices on a home network when the new controlled device is connected to the home network. The discovery process is a process of searching for controlled devices operated on the home network when the new control point is connected to the home network, in order for the control point to control the controlled device. The description process is a process of parsing a service description eXtensible Markup Language (XML) file or a device description XML file through an IP address of a controlled device acquired in the discovery process and recognizing a function of a newly added device in more detail. The control process is a process of, transmitting a control message (action request) for requesting a predetermined service to a corresponding controlled device and receiving a response message (result, variable value) corresponding to the control message by using a Simple Object Access Protocol (SOAP) according to the UPnP device architecture, when the control point desires to provide a specific service through the controlled device. The eventing process is a process of identifying an information change state of the controlled device which has provided the predetermined service according to a control instruction transmitted from the control point.
FIG. 1 is a block diagram illustrating a UPnP telephony system.
The UPnP telephony system includes a telephony service provider 101, a UPnP telephony control point (the control point) 102, a telephony terminal 103, and an electronic device 104. The telephony terminal 103 and the electronic device 104 are located in a space in which a communication with the control point 102 can be performed by using a UPNP protocol.
The telephony service provider 101 provides a telephony service and provides the telephony terminal 103 with an interface for transmitting/receiving a call.
The UPnP telephony control point 102 is a logical software module for controlling a UPnP telephony server 106 and a UPnP telephony client 198 by using a UPnP action. The UPnP telephony control point 102 may be included in a device, such as a PC or a Personal Digital Assistant (PDA), independently of the telephony terminal and the electronic device 104, but may be included in a physical device, such as the telephony terminal 103 or the electronic device 104. When the UPnP telephony control point 102 is included in a physical device, such as the telephony terminal 103 or the electronic device 104, the UPnP telephony control point 102 may directly control the UPnP telephony server 106 or the UPnP telephony client 109 without using a UPnP action.
The UPnP telephony control point 102 determines media, a protocol, and a transmission format to be used in call transmission/reception by using information on a capability of a call data transmission agent included in the UPnP telephony server 106 or the UPnP telephony client 109. The UPnP telephony control point 102 then generates and transmits a profile including the determined media, protocol, and transmission format to the UPnP telephony server 106 or the UPnP telephony client 109, to set an environment of a call data transmission agent included in the telephony terminal 103 or the electronic device 104.
The telephony terminal 103 is a physical device, such as a PC including Voice over IP (VoIP) configured with a Computer Engineering (CE) device including a telephone or software and a mobile communication terminal connected via a communication network, and includes the UPnP telephony server 106 configured with software. Moreover, the telephony terminal 103 controls call transmission/reception with the telephony service provider 101 providing the telephony service by using an interface provided by the corresponding telephony service provider 101.
The electronic device 104 is a CE device, such as a video phone, capable of inputting and outputting voice or a video of a user, and may include a physical device, such as a PC or a television, and includes the UPnP telephony client 109 configured with software. Thus, an embodiment of the present invention may enable a user to conveniently transmit and receive a call by using a home network system.
FIG. 2 illustrates a situation in which users perform video calls by using the UPnP telephony technology in each of their respective homes, respectively. Bob and Alice make video call through mobile phones by using the CE devices, such as televisions, as video and voice input and output devices in their homes. The television includes a video input device, such as a camera, and a video input through the camera is transmitted through a mobile phone via a mobile communication network, e.g., Third Generation Mobile Telecommunications (3G)/Long Term Evolution (LTE) network. Alice's mobile phone receives and then transmits the video to the television and shows the video of Bob to Alice. The video of Alice is also transmitted to Bob's television in the same manner.
In FIG. 2, because the video transmitted to the mobile phone is retransmitted to the television, a resolution of the video is optimized to a size of a screen of the mobile phone. When a low-resolution video is enlarged and displayed in the television, the deterioration of video quality is inevitable.
FIG. 3 illustrates a method of transmitting a high-definition video in the above situation. Information on a television of a counterpart is exchanged and set by using a mobile phone and a high-definition video appropriate for the television is exchanged using a broadband network.
A configuration protocol of FIG. 3 may be specified in a scheme of controlling a mobile phone of a counterpart and receiving or controlling information on a network of the counterpart by using a message in a general scheme of REpresentational State Transfer (REST) using HyperText Transfer Protocol (HTTP).
However, when the configuration protocol of the home network telephony service is specified using the REST scheme, any person can easily find out an IP address of a REST server of the home network. The person can then arbitrarily access the REST server and make a request for and acquire network information on the home network and control a device connected to the home network by using the acquired network information.
Further, the aforementioned problems occur when Short Message Service (SMS) is used instead of a server in the REST scheme.